The invention relates to snowmobile front suspension systems, and, in particular, to improvements in independent front suspension systems of the type employing a rear trailing arm.
A variety of front suspension systems have been employed on snowmobiles over the years. In the early 1980""s the assignee of the present invention introduced to the snowmobiling industry an independent front suspension system utilizing a trailing armxe2x80x94i.e., an elongated arm having its front end connected to the steering spindle, and the rear end pivotably connected to the chassis (see, e.g., Canadian Pat. No. 1,227,823). The trailing arm is oriented generally parallel to the snowmobile""s longitudinal centerline, being angled inwardly at the rear end by only about, e.g., 5xc2x0, reflecting the fact that the ski stance desirably is slightly wider than the body of the snowmobile.
While the trailing arm suspension system has been widely accepted in the snowmobile industry as a very good snowmobile front suspension design, applicants have found that further improvements in the system can be made, providing even greater stability and performance advantages for the rider.
The invention provides a front snowmobile suspension of the type having a ski spindle extending upwardly from a ski, the ski spindle being pivotably carried by the front end of a trailing arm. The front end of the trailing arm is pivotably secured to the chassis by a pair of generally transversely mounted radius rods; each radius rod has an inner end pivotably attached to the chassis and an outer end pivotably attached to the front end of the trailing arm. The radius rods permit upward and downward movement of the front end of the trailing arm. The rear end of the trailing arm is pivotably secured to the chassis at a position sufficiently closer to the chassis centerline than the front end of the trailing arm so that the trailing arm is oriented at an angle of at least about 8xc2x0, and preferably at least about 10xc2x0, with respect to the chassis centerline. At this location the rear end of the trailing arm may be positioned inboard of at least a portion of a body panel (typically the side panel)xe2x80x94i.e. the rear end of the trailing arm is disposed between the body panel and the centerline of the chassis. This unique positioning of the trailing arm has been found to provide increased stability and performance advantages for the rider.